Drawing implement.



N. A. MANTZ.

DRAWING IMPLEMENT.

APPLIOATION nun MAR.1B,1914.

1 10734320 Patented Aug. 18, 19%

awve/wto u NELSON A MANTZ.

THE AORRIS PETERS 60., Pflonrurna. WASHINGTON. D. c.

NELSON A. MANTZ, OF AKRON, OHIO.

DRAXVING IMPLEMENT.

mom-s2.

Specification of Letters Patent.

Patented Aug. 18, 1914.

Application filed March 18, 1914. Serial No. 825,516.

To all whom it may concern Be it known that I, NELSON A. MANTZ, acitizen of the United States, residing at Akron, in the county of Summitand State of Ohio, have invented new and useful Improvements in DrawingImplements, of which the following is a specification.

This invention relates to that class of drawing implements whichembodies straight edges, T-squares, and the like, and has more specificrelation to T-squares.

The object of the invention is to provide a metallic T-square having ablade provided with at least one longitudinally-extending ribconstituting means to receive the hollowed-out portion of a scale toguide and steady the latter during its shifting movement longitudinallyof the drawing implement to hold the indicia-bearing edge of the scaleapproximately flush. with the working edge of the implement. Besidesproviding a guide for the scale and interlocking means for the scale andthe blade of the implement, the rib tends to stiffen and strengthen theimplement so as to prevent distortion.

lVith the foregoing and other objects in view, the invention consists inthe novel construction, combination and arrangement of partsconstituting the invention to be hereinafter specifically described andillustrated in the accompanying drawing which forms a part hereofwherein is shown the preferred embodiment of the invention, but it is tobe understood that changes, variations and modifications can be resortedto which come within the scope of the matter hereinafter claimed.

The drawing presented is a perspective view of a drawing implementembodying this invention showing'the same in connection with atriangularly-formed scale and positioned on an ordinary drawing board.

The invention contemplates the provision of some implement such forinstance, as a straight-edge or a T-square of some light sheet metal,such for instance, as aluminum for the sake of cheapness, lightness, anddurability, provided with one or more ribs extending longitudinallythereof.

In the drawing, the reference numeral 1 denotes the head of a T-squarehere used to illustrate this invention, and preferably formed of metal,and preferably provided with recessed portions 2 for the sake oflightness. Secured to the head 1 is a blade 3 held in position throughthe medium of hold-fast devices t and of a suitable or preferred length.The blade 3 is preferably formed of sheeted aluminum and is alsoprovided with one or more upwardly-extending ribs 5 and 6 formed byupsetting the metal. One of the ribs, say for instance, 5, in thedrawing, is positioned at such a point with respect to the working edge7 of the blade of the T-square that when a scale 8 of ordinaryconstruction and provided with a concave groove 9, is positionedthereon, the longitudinally-extending rib 5 will engage in the groove 9of the inner face of the scale and form to a certain extent aninterlocking engagement between the two, whereby the scale may be slidlongitudinally and yet maintain itself at all times in a positionrelatively fixed transversely with respect to the working edge 7 of theblade. Under ordinary circumstances, the ribs 5 will be so positionedwith respect to the working edge 7 that the indicia-bearing portionutilized by the draftsman will be approximately fiush with the workingedge 7, so as to be readily read by the draftsman.

It is apparent that instead of utilizing a triangularly-formed scale 8,as shown, a flat scale provided with a cooperating portion to receivethe rib 5 may be employed, so long as the groove in the scale issuitably positioned as to bring the indicia-bearing portion of the scalein substantial alinement with the working edge 7.

The usefulness of the invention is apparent upon inspection, but it maybe pointed out that whenever it is necessary to remove the scale for anypurpose, replacement of the same in the exact position on the T- squareis rendered comparatively easy and the efliciency of the draftsman isincreased.

I claim:

The combination with a drawing implement such for instance as aT-square, embodying a blade formed of a strip of light sheet metalhaving a working edge, and provided with an integral upwardly-projectingrib on its upper face formed by bending up the metal of the blade, saidrib extending longitudinally thereof and parallel with said workingedge, and a scale mounted on the upper face of said blade and providedwith a longitudinally-extending groove adapted to freely receive saidrib, the relative position of the rib on the blade and the groove in thescale being such that When my hanclin presence of two subscribing Witthescale 1s p0s1t10ned 0n the blade the 111- nesses.

clieia-bearin edge of the scale Will be flush with the w rking edge ofthe blade, said NELSON 'MANTZ' scale being freely and bodily removablever- Vitnesses: tically from engagement with said blade. C. E. HUMPHREY,

In testimony whereof I have hereunto set A. L. MCCLINTOCK.

Copies of this patent may be blitahie'd 61 five cents afi; by admss'ingthe Gommissioner of Patents.

' Washifiifffifi; D. G.

